title: Neurochemical abnormalities in unmedicated bipolar depression and mania: a 2D 1H MRS investigation.
abstract: The neurobiology and neurochemistry of bipolar disorder and its different phases are poorly understood. This study investigated metabolite abnormalities in both unmedicated bipolar depression as well as mania using 2D 1H magnetic resonance spectroscopy imaging (MRSI). MRSI data were obtained from 24 unmedicated bipolar disorder (BP) subjects (12 (hypo)manic (BPM)) and 12 depressed (BPD), and 20 closely matched healthy controls. 2D 1H MRSI data were collected from a 15-mm axial slice placed along the anterior commissure-posterior commissure (AC-PC) line to measure brain metabolites bilaterally in the thalamus and also the anterior and posterior cingulate cortex (ACC and PCC). Brain Lac/Cr levels were significantly increased in the BP group as a whole compared to healthy controls. Glutamate abnormalities varied across bipolar state as well as brain region: significantly increased Glx/Cr values were found in the left thalamus in BPD, but BPM had decreased Glu/Cr and Glx/Cr levels in the PCC when compared to healthy controls and decreased Glu/Cr levels even when compared to the BPD subjects group. The findings of the study point to state-related abnormalities of oxidative and glutamate metabolism in bipolar disorder.
authors.affiliation: Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.forename: Ulrike
authors.initials: U
authors.lastname: Dydak
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Harezlak
authors.forename: Jonathan
authors.initials: J
authors.lastname: Nixon
authors.forename: Mario
authors.initials: M
authors.lastname: Dzemidzic
authors.forename: Abigail D
authors.initials: AD
authors.lastname: Gunn
authors.forename: Harish S
authors.initials: HS
authors.lastname: Karne
authors.forename: Amit
authors.initials: A
authors.lastname: Anand
mesh_terms: D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D001714:Bipolar Disorder / Q000473:pathology*; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D003401:Creatine / Q000378:metabolism*; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019344:Lactic Acid / Q000378:metabolism*; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D014316:Tritium; D055815:Young Adult
chemical_list: D014316:Tritium; D001224:Aspartic Acid; D019344:Lactic Acid; D018698:Glutamic Acid; C000179:N-acetylaspartate; D003401:Creatine
keywords: Bipolar disorder; Depression; Glutamate; Lactate; MRS; Mania